So, I'm currently maining Blood DK and that's the spec that I've gotten my 4 legends on. I do occasionally use UH and was wondering which of my legends would be most effective for it. Just a foreword, all of the gear that the legends replace is about equal; all 915-920 and don't cause any major stat changes so its not like using one legend over another causes me to use a bad piece. I have Soul of the Deathlord, which is the one I use most on UH, and I have Shackles of Bryndaor, Archimonde's Hatred Reborn, and Prydaz, Xavaric's Magnum Opus. Does the Shackles passive work on UH, if so, could that be a better boost for Val'kyr[Dark Arbiter Talent] (b/c you can cycle more RP)? Other than that I'm just wondering which out weighs the other, STR or the secondaries?
Edit: and just in case it makes a difference, my talent build is; http://www.wowhead.com/talent-calc/death-knight/unholy/c75z

I figured I'd do a Part 2 of this since I've managed to move from having never tanked before to now I can't get enough of it.
I've noticed a few things and wanted as much input as I can get. What has struck me so far is the lack of healers running PUGs at the lvl 60-ish area. It takes forever to get a PUG group together and I haven't been able to keep a healer with us more than 1 run through. I've made some DPS friends through PUGs which is pretty cool, but what is up with the healers???
The second thing is how my damage relates to a few other classes at about the same level. I'm currently lvl 67. I'm able to hold aggro nearly most of the time. I have some PUG members than have a pet with taunt or something but for the most part I am good to go. What I will see are Death Knights and some Warlock/Mages that seem to be doing crazy damage while only being a level or 2 higher than I am. Is that normal or am I undergeared? I haven't quite downloaded a damage meter just yet but from watching the health bar on the enemies I've noticed that those 2 can do some big damage by themselves! So is it a gear issue with me, is it just the nature of their class at that level or are they over-geared with extra goodies figuring their main has helped pay for their current state of their equipment? And with that, any recommendations or just hang in there until I get much higher level when better equipment appears? I have Heirloom for my chest, back, shoulders, weapon and trinkets. I haven't really found any quest gear or dungeon drops that is better that what I have now.
I can't say Thank You enough to everybody that posted advice and encouragement in my first thread. It was very helpful and I've taken a lot of it to heart and put it to work. I have had so much fun doing this...as like most things in life you are leery of...once you try it you only regret NOT doing it sooner.